Abstract：
This paper describes an approach based on the method of terahertz time-domain spectroscopy, which allows the analysis of dynamical hydration shells of proteins with a thickness of 1-2 nm. Using the example of bovine serum albumin in three conformations, it is shown that the hydration shells of the protein are characterized by increased binding of water molecules in the primary hydration layers, and in more distant areas of hydration, on the contrary, the water structure is somewhat destroyed. The fraction of free or weakly bound molecules, usually observed in the structure of liquid water in hydration shells, become more numerous but its average binding is greater than in undisturbed water. The energy distribution of hydrogen bonds in hydration shells is narrowed compared to undisturbed water. All these manifestations of hydration are most pronounced for the native conformation of the protein. Also, the hydration shells of the native protein are characterized by a smaller number of hydrogen bonds and a tendency to decrease their average energy compared to non-native conformations. The fact of a pronounced peculiarity of the hydration shells of the protein in the native conformation has been noted for different proteins before. However, the methodological approach used in this work for the first time allowed this peculiarity to be described by specific parameters of the intermolecular structure and dynamics of water.
摘要：
本文介绍了一种基于太赫兹时域光谱的方法,它允许分析厚度为1-2nm的蛋白质的动态水合壳。以三种构象的牛血清白蛋白为例，结果表明，蛋白质的水合壳的特征是主要水合层中水分子的结合增加，在更遥远的水合区域，相反,水结构有些被破坏。自由或弱结合分子的分数，通常在水合壳中的液态水结构中观察到，变得更多，但其平均结合大于在未受干扰的水中。与未受干扰的水相比，水合壳中氢键的能量分布变窄。水合的所有这些表现对于蛋白质的天然构象是最明显的。此外，与非天然构象相比,天然蛋白质的水合壳的特征在于较少数量的氢键和降低其平均能量的趋势。以前对于不同的蛋白质已经注意到天然构象中的蛋白质的水合壳的明显特性的事实。然而,这项工作中首次使用的方法论方法允许通过水的分子间结构和动力学的特定参数来描述这种特性。
